The present invention relates to certain novel substituted benzene derivatives having at least one benzene ring substituted by at least one 3,3,3-trifluoropropyl group and to a novel process for producing the above-mentioned substituted benzene derivative.
The substituted benzene derivatives having benzene ring(s) substituted by 3,3,3-trifluoropropyl group(s) are useful for a variety of purposes. However, as an instance for synthesizing aromatic compounds having benzene ring(s) substituted by 3,3,3-trifluoropropyl group, only a process (U.S. Pat. No. 3,080,428) has been proposed in which 3,3,3-trifluoropropyl ether, (CF.sub.3 CH.sub.2 CH.sub.2).sub.2 O, is brought into reaction with benzene in the presence of hydrogen fluoride to form 3,3,3-trifluoropropylbenzene. Moreover, since in the above-mentioned process, water is formed in the reaction, the catalytic reactivity during the reaction is reduced and the recovery of the used catalyst is difficult. In addition, since the starting material of the reaction, 3,3,3-trifluoropropyl ether is synthesized by a low-yield (50 to 60%) reaction of hydrogen fluoride, formaldehyde or its polymer and very expensive vinylidene fluoride, the thus synthesized 3,3,3-trifluoropropyl ether is highly expensive.
It is an object of the present invention to produce a trifluoropropyl derivative of mono-substituted benzene represented by the formula: ##STR2## wherein R is halogen atom, hydroxy, trifluoromethyl, n-octyl, n-dodecyl, or phenoxy group not substituted or mono-substituted by 3,3,3-trifluoropropyl group, and n is an integer of 1, 2 or 3, with the proviso that the total number of 3,3,3-trifluoropropyl group in said derivative of mono-substituted benzene is at most 3. A further object of the present invention is to provide a process for producing the above-mentioned derivative of mono-substituted benzene having at least one benzene ring substituted by at least one 3,3,3-trifluoropropyl group which comprises bringing a mono-substituted benzene of the formula, ##STR3## wherein R.sup.1 is halogen atom, hydroxy, phenoxy, trifluoromethyl, n-octyl or n-dodecyl group, into reaction with 3,3,3-trifluoropropylene in the presence of an acid catalyst selected from the group consisting of hydrogen fluoride, boron trifluoride and a mixture thereof. Other object is to provide a 3,3,3-trifluoropropyl derivative of n-octyl- or n-dodecylbenzene obtained by bringing n-octylbenzene or n-dodecylbenzene into reaction with 3,3,3-trifluoropropylene in the presence of an acid catalyst selected from the group consisting of hydrogen fluoride, boron trifluoride and a mixture thereof.